A wide variety of devices are employed to concentrate the gold present in certain rivers and streams of the world. The two most common devices currently in use are the sluice and the gold pan. The gold sluices of prior art produce concentrates that can be ninety-five percent or more waste minerals. These waste minerals are mostly black sand. The concentrates produced by prior art are difficult to separate into values and waste products. One problem is that a skilled panner must then reduce the concentrates to super-concentrates. This stage of concentration is labor intensive and requires skill. A separate device may be bought and employed to reduce the concentrates to super-concentrates much faster than panning by hand. At the super-concentrate stage the gold produced can be seen and the productivity of the prospect calculated. Prospectors often work with time constraints. Some must prove profitability to their investors.
A sluice is a water channel, typically controlled at its head by a gate, allowing water or other liquids to flow through. Sluice boxes (also referred to herein as “sluices” for the sake of brevity) are often used in the recovery of black sands, gold, and other minerals from placer deposits during placer mining operations. They can be small scale, as used in prospecting, or much larger, as in commercial operations, where the material can be screened first using a trammel or screening plant. Typical sluices have transverse riffles over a carpet which trap heavy materials, gemstones, and other valuable minerals. Various sluices have different types of riffles. Riffles are obstacles in a flow of water.